I am Going to replace my oil pump and rear main seal. I do not intent on taking the crank out. I don’t mind bucking up for quality parts but there seems to be lots of choice so any advice you guys have would be appreciated. Thanks

I've had no problems with the Melling M54DS oil pump.

https://www.amazon.com/Melling-M54DS-Replacement-Oil-Pump/dp/B000C4PO6E

Some like to replace the oil pump driveshaft, tho I've never broke a stock one.

https://www.amazon.com/Melling-IS54A-Oil-Pump-Driveshaft/dp/B000C4LRR4

I repaired/replaced one rope seal, with engine in car.

Went by the instructions in the 1969 Pontiac service manual. Made a tool to drive the ends of the rope up into the groove, as per instructions. Then you cut short pieces off one of the supplied pieces of rope, and packed them into the ends of the groove as much as possible, then cut 'em off even with the block.

Then install the other piece of rope into the groove in the cap, and trim off ends, in the usual manner.

The Best Gasket brand is now considered the best rope seal on the market.

http://www.bestgasket.com/pop_up_picture.asp?PartNumber=6380S

https://butlerperformance.com/i-24452895-best-gasket-braided-teflon-graphite-rope-seal-for-326-400-bga-6380x.html?ref=category:1234758

https://www.ebay.com/itm/Pontiac-40...Main-Bearing-Seal-Set-BEST-/171134712932

Thanks very much I really appreciate your input.

Be prepared for the worst on replacing the rear main seal. On these Pontiac engines that have been together 40 something years and with the crank out, i have had to use a screwdriver and wire wheel in the angle grinder to remove all of the rope seal that is basically glued to the groove in the block.

Ok Thanks! That’s good food for thought, I have had to use a die grinder and a small wire wheel to clean and prep other parts so stands to reason. This engine has not been apart or out of the car since new. I’ll keep you guys posted